According to Google Trends, the number of searches for the term "blue light" has increased since 2004. 1 This indicates that concerns about blue light and attempts at obtaining protection from this potential threat have been on the rise. From computer filters-to makeup products and eye lenses, consumers are searching for the best items to protect themselves. 2 Makeup and skin care products with blue light claims have significantly grown by about 170% in 2020 and are expected to continue to grow as more scientific evidence is published about the effects of blue light. 3 2 | WHAT IS B LUE LI G HT ? Blue light is emitted visible light in wavelengths between 400 and 500 nm. 4 Blue light is generally referred to as high energy visible light as it is at the shortest wavelength, thus the highest energy, in the visible light spectrum (Figure 1). 5 This is not to get confused with the further classification as "low energy" or "high energy" within the 400 to 500 nm range. When at the higher end of the blue light range the light is known as low energy, while at the lower end it is known as high energy-yet blue light altogether is the highest in energy compared with the rest of the visible light spectrum. Also, as the name suggests, blue light is observed as blue. The main source of blue light is sunlight. Additional sources include digital screens, such as cellphones, computers, laptops, and TVs; light-emitting diodes

Background: There are numerous cosmetic ingredients that have been identified to have blue light protection benefits. The urge to learn more about blue light protection claims has led to several substantiation test methods that can be utilized by companies to prove product efficacy. Aims: Part II of this article provides up-to-date information on cosmetic ingredients that can provide protection from blue light, and methods companies can use to substantiate blue light protection claims. Methods: An Internet search was completed using the Google Scholar database and a cosmetic ingredient supplier database (UL Prospector) for ingredients and relevant literature. Results: Multiple ingredient categories, for example, algae-derived ingredients, UV filters, botanical extracts, antioxidants, and vitamins, are available on the market to fight against blue light-induced skin damage. There is not a formal standardized method to test for blue light protection; however, spectrophotometers, imaging devices, measuring oxidative stress, and visual evaluations are some of the methods being used today. Conclusions: The number of ingredients launched for blue light protection and new methods developed to test products for blue light protection claims is expected to increase in the near future as we are learning more about the mechanism of damage that occurs in the skin upon blue light exposure.

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OBJECTIVE Waxes are used as structuring agents in lipsticks. There are a variety of waxes combined in a single lipstick to provide good stability, pleasant texture and good pay‐off. Due to a significant growth for natural, green and sustainable products, there is a constant search for alternatives to animal‐derived and petroleum‐derived ingredients. In this study, a green, non‐animalderived wax, namely long‐chain ketones (referred to as alkenones), sourced from marine microalgae was formulated into lipsticks and evaluated as a structuring agent. METHODS Alkenones were used as a substitute for microcrystalline wax, ozokerite and candelilla wax, typical structuring agents. In total, 384 lipsticks were formulated: L1 (control, no alkenones), L2 (alkenones as a substitute for ozokerite), L3 (alkenones as a substitute for microcrystalline wax) and L4 (alkenones as a substitute for candelilla wax). Products were tested for hardness (bending force), stiffness, firmness (needle penetration), pay‐off (using a texture analyser and a consumer panel), friction, melting point and stability for 12 weeks at 25 and 45°C. RESULTS Alkenones influenced each characteristic evaluated. In general, lipsticks with alkenones (L2‐L4) became softer and easier to bend compared to the control (L1). In terms of firmness, lipsticks were similar to the control, except for L4, which was significantly (P < 0.05) firmer. The effect on pay‐off was not consistent. L2 and L3 had higher pay‐off to skin and fabric than L1. In addition, L4 had the lowest amount transferred, but it still had the highest colour intensity on skin. Alkenones influenced friction (glide) positively; the average friction decreased for L2‐L4. The lowest friction (i.e. best glide) was shown in L4. Melting point of the lipsticks was lower when alkenones were present. Overall, L4, containing 7% of 4 alkenones in combination with microcrystalline wax, ozokerite and carnauba wax, was found to have the most desirable attributes, including ease of bending, high level of firmness, low pay‐off in terms of amount, high colour intensity on skin and low friction (i.e. better glide). Consumers preferred L4 the most overall. CONCLUSION Results of this study indicate that alkenones offer a sustainable, non‐animal and non‐petroleum‐derived choice as a structuring agent for lipsticks.

Objective Green and sustainable trends are growing and with that the demand for naturally derived ingredients is rising. Dispersing agents are essential components of lipsticks due to their ability to wet pigment particles, reduce agglomerates and prevent re‐agglomeration by stabilizing pigment particles. In this study, meadowfoam seed oil was evaluated as a pigment‐dispersing agent for lipsticks and compared with castor oil and octyldodecanol. Methods Dispersions of Red 7 Lake were formulated with 20, 30 and 40% solid content using castor oil, octyldodecanol or meadowfoam seed oil. Particle size, viscosity, spreadability, wetting, oil absorption and colour were measured. Four of the nine dispersions were then formulated into lipsticks, including all the 30% pigment dispersions and the 40% dispersion with meadowfoam seed oil. Lipsticks were tested for hardness, pay‐off, friction, rheology, colour and stability for 4 weeks. Results Average particle size was between 6 and 9 µm across the dispersions. The castor oil dispersions were more viscous, stickier and harder to spread than the other dispersions. The wetting contact angle was very low for all three dispersing agents, indicating that all of the oils wet the pigment well. The lipsticks varied in hardness, as expected, based on differences in the viscosity of the dispersing agents, and oil absorption of the powder. Red 7 Lake absorbed the highest amount of castor oil, which contributed to higher stick hardness. The castor oil lipstick and the meadowfoam seed oil lipstick containing 40% pigment were the hardest and most elastic. The octyldodecanol lipstick was the softest. Friction was the lowest for the meadowfoam seed oil lipstick containing 40% pigment, while pay‐off was the highest for the octyldodecanol lipstick. The colour of the lipsticks as a stick and after being spread on paper was very similar. Conclusion While the chemical composition and physicochemical properties of the dispersing agents were different, all three dispersing agents studied formed dispersions and lipsticks with appropriate characteristics. Meadowfoam seed oil's performance was qualitatively and quantitatively similar to castor oil and octyldodecanol. By modifying the amount of pigment and dispersing agent used, lipsticks that have similar characteristics to commercial products can be formulated.